Heat dissipating device

ABSTRACT

A heat dissipating device includes a chamber body, a heat sink, a pipe, a first capillary structure and N vapor channels. The chamber body has an evaporation chamber and a compensation chamber, wherein the evaporation chamber has a vapor outlet and the compensation chamber has a liquid inlet. The heat sink is disposed on an outer wall of a first side of the chamber body and at least covers the compensation chamber. The pipe is installed within the heat sink, wherein a first end of the pipe is connected to the vapor outlet and a second end of the pipe is connected to the liquid inlet. The first capillary structure is formed in the evaporation chamber. The N vapor channels are formed in the first capillary structure. The N vapor channels and the compensation chamber are isolated by the first capillary structure.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a heat dissipating device and, more particularly, to a loop-heat-pipe type heat dissipating device.

2. Description of the Prior Art

Heat dissipating device is a significant component for electronic products. When an electronic product is operating, the current in circuit will generate unnecessary heat due to impedance. If the heat is accumulated in the electronic components of the electronic product without dissipating immediately, the electronic components may get damage due to the accumulated heat. Therefore, the performance of heat dissipating device is a significant issue for the electronic product.

So far the heat dissipating device used in the electronic product usually consists of a heat pipe, a heat dissipating fin and a heat dissipating fan, wherein one end of the heat pipe contacts the electronic component, which generates heat during operation, the other end of the heat pipe is connected to the heat dissipating fin, and the heat dissipating fan blows air to the heat dissipating fin so as to dissipate heat. However, since heat generated by the electronic component increases per unit time while calculation speed of the electronic component increase, the conventional heat dissipating device cannot dissipate heat effectively form the electronic component such that heat will be accumulated in the electronic component accordingly. Therefore, how to dissipate heat from the electronic component much more rapidly becomes a significant issue while designing the heat dissipating device.

SUMMARY OF THE INVENTION

The invention provides a heat dissipating device for solving the aforesaid problems.

According to an embodiment of the invention, a heat dissipating device comprises a chamber body, a heat sink, a pipe, a first capillary structure and N vapor channels, wherein N is a positive integer. The chamber body has an evaporation chamber and a compensation chamber, wherein the evaporation chamber has a vapor outlet and the compensation chamber has a liquid inlet. The heat sink is disposed on an outer wall of a first side of the chamber body and at least covers the compensation chamber. The pipe is installed within the heat sink, wherein a first end of the pipe is connected to the vapor outlet and a second end of the pipe is connected to the liquid inlet. The first capillary structure is formed in the evaporation chamber. The N vapor channels are formed in the first capillary structure. The N vapor channels and the compensation chamber are isolated by the first capillary structure.

In this embodiment, the heat dissipating device may further comprise a vapor collecting space formed in the evaporation chamber and communicating with the N vapor channels and the vapor outlet.

As mentioned in the above, the heat sink of the invention is disposed on the outer wall of the chamber body and at least covers the compensation chamber and the pipe of the invention is installed within the heat sink, such that the heat sink not only can cool vapor within the pipe but also can absorb heat leak within the compensation chamber so as to enhance heat dissipating efficiency of the heat dissipating device. Furthermore, sine the vapor channels and the compensation chamber are isolated by the capillary structure, the vapor generated in the vapor channels cannot flow back to the compensation chamber. Accordingly, pressure difference between the evaporation chamber and the compensation chamber can be maintained so as to prevent the heat dissipating device from failing due to reduced pressure difference. Moreover, the invention utilizes the vapor collecting space to communicate with the vapor channels and the vapor outlet such that vapor generated in all vapor channels can flow into the pipe from the vapor outlet through the vapor collecting space. Accordingly, heat dissipating efficiency of the heat dissipating device can be enhanced effectively.

These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating a heat dissipating device according to an embodiment of the invention.

FIG. 2A is a top view illustrating the heat dissipating device shown in FIG. 1.

FIG. 2B is cross-sectional view illustrating the heat dissipating device along X-X line shown in FIG. 2A.

FIG. 2C is a cross-sectional view illustrating the heat dissipating device along Y-Y line shown in FIG. 2A.

FIG. 3 is an assembly view illustrating the chamber body and the first capillary structure shown in FIG. 2B from different view angles.

FIG. 4 is a cross-sectional view illustrating a heat dissipating device according to another embodiment of the invention.

FIG. 5 is a cross-sectional view illustrating a heat dissipating device according to another embodiment of the invention.

FIG. 6 is a cross-sectional view illustrating a heat dissipating device according to another embodiment of the invention.

FIG. 7 is a cross-sectional view illustrating a heat dissipating device according to another embodiment of the invention.

FIG. 8 is a cross-sectional view illustrating a heat dissipating device according to another embodiment of the invention.

FIG. 9 is a cross-sectional view illustrating a heat dissipating device according to another embodiment of the invention.

DETAILED DESCRIPTION

Referring to FIGS. 1 to 3, FIG. 1 is a perspective view illustrating a heat dissipating device 1 according to an embodiment of the invention, FIG. 2A is a top view illustrating the heat dissipating device 1 shown in FIG. 1, FIG. 2B is cross-sectional view illustrating the heat dissipating device 1 along X-X line shown in FIG. 2A, FIG. 2C is a cross-sectional view illustrating the heat dissipating device 1 along Y-Y line shown in FIG. 2A, and FIG. 3 is an assembly view illustrating the chamber body 10 and the first capillary structure 16 shown in FIG. 2B from different view angles.

As shown in FIGS. 1 to 3, the heat dissipating device 3 comprises a chamber body 10, a heat sink 12, a pipe 14, a first capillary structure 16, N vapor channels 18 and a vapor collecting space 20, wherein N is a positive integer. The chamber body 10 has an evaporation chamber 100 and a compensation chamber 102, wherein the evaporation chamber 100 has a vapor outlet 104 and the compensation chamber 102 has a liquid inlet 106. The heat sink 12 is disposed on an outer wall 108 of a first side S1 of the chamber body 10 and at least covers the compensation chamber 102. In this embodiment, the heat sink 12 covers the compensation chamber 102 and the evaporation chamber 100 at the same time. In another embodiment, the heat sink 12 may only cover the compensation chamber 102. The heat sink 12 and the compensation chamber 102 maybe served as a vapor chamber as long as the heat sink 12 covers the compensation chamber 102. Accordingly, the heat sink 12 can absorb heat leak within the compensation chamber 102 so as to enhance heat dissipating efficiency of the heat dissipating device 1. The heat sink 12 may comprise a plurality of heat dissipating fins 120. In practical applications, a working fluid (not shown), such as water or other fluids with low viscosity, is filled in the chamber body 10.

The pipe 14 is installed within the heat sink 12 such that the heat sink 12 can cool vapor within the pipe 14. A first end 140 of the pipe 14 is connected to the vapor outlet 104 of the evaporation chamber 100 and a second end 142 of the pipe 14 is connected to the liquid inlet 106 of the compensation chamber 102. Accordingly, when the working fluid is evaporated by heat to be transformed into vapor, the vapor can flow into the pipe 14 from the vapor outlet 104. Then, the vapor is cooled by the heat sink 12 to be transformed into liquid and the liquid flows into the compensation chamber 102 of the chamber body 10 from the liquid inlet 106. Since the pipe 14 and the chamber body 10 are configured in a loop type, the heat dissipating device 1 may be called as loop-heat-pipe type heat dissipating device. In this embodiment, a pipe diameter D1 of the first end 140 is larger than a pipe diameter D2 of the second end 142 (as shown in FIG. 2A) so as to ensure that a pressure difference at the first end 140 is smaller than a pressure difference at the second end 142. Accordingly, the vapor and liquid can circulate in the chamber body 10 well.

The first capillary structure 16 and the vapor collecting space 20 are formed in the evaporation chamber 100. The N vapor channels 18 are formed in the first capillary structure 16. In this embodiment, there are twelve vapor channels 18 formed in the first capillary structure 16 (i.e. N=12), arranged in equal distance and close to an inner wall 110 of a second side S2 of the chamber body 10, wherein the second side S2 is opposite to the aforesaid first side S1. As shown in FIGS. 2B and 2C, a heat source 3 is attached on an outer wall 112 of the second side S2 of the chamber body 10. In other words, the vapor channels 18 of the invention are close to the heat source 3. Thermal resistance is lower while the vapor channels 18 are closer to the heat source 3. Accordingly, the liquid within the first capillary structure 16 can be evaporated by heat rapidly and then be transformed into vapor in the vapor channels 18 so as to enhance heat dissipating efficiency. It should be noted that the number and arrangement of the vapor channels can be determined based on practical applications and are not limited to the embodiment shown in the figures.

As shown FIGS. 2B and 3, all of the vapor channels 18 and the compensation chamber 102 are isolate by the first capillary structure 16. That is to say, each of the vapor channels 18 does not communicate with the compensation chamber 102 such that the vapor generated in each of the vapor channels 18 cannot flow back to the compensation chamber 102. Accordingly, pressure difference between the evaporation chamber 100 and the compensation chamber 102 can be maintained so as to prevent the heat dissipating device 1 from failing due to reduced pressure difference between the evaporation chamber 100 and the compensation chamber 102. Furthermore, the vapor collecting space 20 communicates with all of the vapor channels 18 and the vapor outlet 104 such that the vapor generated in each of the vapor channels 18 can flow into the pipe 14 from the vapor outlet 104 through the vapor collecting space 20, so as to enhance heat dissipating efficiency of the heat dissipating device 1.

In this embodiment, a cross-section of each of the vapor channels 18 is circular, as shown in FIG. 2C. In another embodiment, a cross-section of each of the vapor channels 18 may be rectangular, polygonal or arc-shaped.

Referring to FIG. 4 along with FIG. 2C, FIG. 4 is a cross-sectional view illustrating a heat dissipating device 1′ according to another embodiment of the invention. The difference between the heat dissipating device 1′ and the aforesaid heat dissipating device 1 is that M of the N vapor channels 18 of the heat dissipating device 1′ are located on the inner wall 110 of the second side S2 of the chamber body 10 (i.e. N=12 and M=N). Furthermore, a cross-section of each of the vapor channels 18 is half-circular. Since the vapor channels 18 are located on the inner wall 110 of the second side S2 of the chamber body 10, the liquid within the first capillary structure 16 can be evaporated by heat rapidly and then be transformed into vapor in the vapor channels 18 so as to enhance heat dissipating efficiency. It should be noted that the same elements in FIG. 4 and FIG. 2C are represented by the same numerals, so the repeated explanation will not be depicted herein again.

Referring to FIG. 5 along with FIG. 2C, FIG. 5 is a cross-sectional view illustrating a heat dissipating device 1″ according to another embodiment of the invention. The difference between the heat dissipating device 1″ and the aforesaid heat dissipating device 1 is that M of the N vapor channels 18 of the heat dissipating device 1′ are located on the inner wall 110 of the second side S2 of the chamber body 10 and P of the N vapor channels 18 are located on the inner wall 114 of the first side S1, wherein P is a positive integer and a sum of P and M is smaller than or equal to N. In this embodiment, twelve of twenty-four vapor channels 18 are located on the inner wall 110 of the second side S2 of the chamber body 10 and the other twelve of twenty-four vapor channels 18 are located on the inner wall 114 of the first side S1 (i.e. N=24 and P+M=N). Furthermore, a cross-section of each of the vapor channels 18 is rectangular. Since each of the vapor channels 18 is rectangular, the pressure difference of the vapor channel 18 can be reduced so as to enhance heat dissipating efficiency. Moreover, the vapor channels 18 on opposite sides may be arranged symmetrically or interlacedly and it depends on practical applications. It should be noted that the same elements in FIG. 5 and FIG. 2C are represented by the same numerals, so the repeated explanation will not be depicted herein again.

Referring to FIG. 6 along with FIG. 2C, FIG. 6 is a cross-sectional view illustrating a heat dissipating device 1′″ according to another embodiment of the invention. The difference between the heat dissipating device 1′″ and the aforesaid heat dissipating device 1 is that M of the N vapor channels 18 of the heat dissipating device 1′″ are located on the inner wall 110 of the second side S2 of the chamber body 10, P of the N vapor channels 18 are located on the inner wall 114 of the first side S1, and Q of the N vapor channels 18 are located between the M vapor channels 18 and the P vapor channels 18, wherein Q is a positive integer and a sum of Q, P and M is equal to N. In this embodiment, twelve of thirty-five vapor channels 18 are located on the inner wall 110 of the second side S2 of the chamber body 10, twelve of thirty-five vapor channels 18 are located on the inner wall 114 of the first side S1, and the other eleven of thirty-five vapor channels 18 are located between the twenty-four vapor channels 18 on opposite sides (i.e. N=35 and Q+P+M=N). Furthermore, a cross-section of each of the vapor channels 18 is rectangular. It should be noted that the same elements in FIG. 6 and FIG. 2C are represented by the same numerals, so the repeated explanation will not be depicted herein again.

Referring to FIG. 7 along with FIG. 2B, FIG. 7 is a cross-sectional view illustrating a heat dissipating device 5 according to another embodiment of the invention. The difference between the heat dissipating device 5 and the aforesaid heat dissipating device 1 is that the heat dissipating device 5 further comprises a second capillary structure 50 formed in the compensation chamber 102 and located on the inner wall 110 of the second side S2 of the chamber body 10. Once heat leak is generated in the compensation chamber 102, the liquid within the second capillary structure 50 will be evaporated by heat and then be transformed into vapor. Consequently, heat leak generated in the compensation chamber 102 can be dissipated by the heat sink 102 outside of the compensation chamber 102 so as to enhance heat dissipating efficiency. It should be noted that the same elements in FIG. 7 and FIG. 2B are represented by the same numerals, so the repeated explanation will not be depicted herein again.

Referring to FIG. 8 along with FIG. 7, FIG. 8 is a cross-sectional view illustrating a heat dissipating device 5′ according to another embodiment of the invention. The difference between the heat dissipating device 5′ and the aforesaid heat dissipating device 5 is that the heat dissipating device 5′ further comprises a third capillary structure 52 and a plurality of support pillars 54. The third capillary structure 52 is formed in the compensation chamber 102 and located on the inner wall 114 of the first side S1. The support pillars 54 are formed in the compensation chamber 102 and connect the second capillary structure 50 and the third capillary structure 52. The support pillars 54 can prevent the compensation chamber 102 from cracking due to compression. In this embodiment, after the heat sink 12 outside of the compensation chamber 102 takes heat away, the vapor will be congealed to form glob on the third capillary structure 52 and then the glob will flow to the second capillary structure 50 along the support pillars 54 so as to accelerate the cycle of vapor and liquid within the compensation chamber 102. Accordingly, heat dissipating efficiency can be enhanced. It should be noted that the same elements in FIG. 8 and FIG. 7 are represented by the same numerals, so the repeated explanation will not be depicted herein again.

Referring to FIG. 9 along with FIG. 8, FIG. 9 is a cross-sectional view illustrating a heat dissipating device 5″ according to another embodiment of the invention. The difference between the heat dissipating device 5″ and the aforesaid heat dissipating device 5′ is that the heat dissipating device 5″ further comprises a plurality of fourth capillary structures 56. Each of the fourth capillary structures 56 is formed around one of the support pillars 54 and connects the second capillary structure 50 and the third capillary structure 52. In this embodiment, after the heat sink 12 outside of the compensation chamber 102 takes heat away, the vapor will be congealed to form glob on the third capillary structure 52 and then the glob will flow to the second capillary structure 50 along the fourth capillary structures 56 so as to accelerate the cycle of vapor and liquid within the compensation chamber 102. Accordingly, heat dissipating efficiency can be enhanced. It should be noted that the same elements in FIG. 9 and FIG. 8 are represented by the same numerals, so the repeated explanation will not be depicted herein again.

It should be noted that the aforesaid first capillary structure 16, second capillary structure 50, third capillary structure 52 and fourth capillary structures 56 may be formed by, but not limited to, a metal powder sintering process. It depends on practical applications.

Compared with the prior art, the heat sink of the invention is disposed on the outer wall of the chamber body and at least covers the compensation chamber and the pipe of the invention is installed within the heat sink, such that the heat sink not only can cool vapor within the pipe but also can absorb heat leak within the compensation chamber so as to enhance heat dissipating efficiency of the heat dissipating device. Furthermore, sine the vapor channels and the compensation chamber are isolated by the capillary structure, the vapor generated in the vapor channels cannot flow back to the compensation chamber. Accordingly, pressure difference between the evaporation chamber and the compensation chamber can be maintained so as to prevent the heat dissipating device from failing due to reduced pressure difference. Moreover, the invention utilizes the vapor collecting space to communicate with the vapor channels and the vapor outlet such that vapor generated in all vapor channels can flow into the pipe from the vapor outlet through the vapor collecting space. Accordingly, heat dissipating efficiency of the heat dissipating device can be enhanced effectively. Still further, the invention may form capillary structures in the compensation chamber so as to accelerate the cycle of vapor and liquid within the compensation chamber. Accordingly, heat dissipating efficiency can be enhanced.

Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims. 

What is claimed is:
 1. A heat dissipating device comprising: a chamber body having an evaporation chamber and a compensation chamber, the evaporation chamber having a vapor outlet, the compensation chamber having a liquid inlet; a heat sink disposed on an outer wall of a first side of the chamber body and at least covering the compensation chamber; a pipe installed within the heat sink, a first end of the pipe being connected to the vapor outlet, a second end of the pipe being connected to the liquid inlet; a first capillary structure formed in the evaporation chamber; and N vapor channels formed in the first capillary structure, the N vapor channels and the compensation chamber being isolated by the first capillary structure, N being a positive integer.
 2. The heat dissipating device of claim 1 further comprising a vapor collecting space formed in the evaporation chamber and communicating with the N vapor channels and the vapor outlet.
 3. The heat dissipating device of claim 1, wherein M of the N vapor channels are located on an inner wall of a second side of the chamber body, M is a positive integer smaller than or equal to N, and the second side is opposite to the first side.
 4. The heat dissipating device of claim 3, wherein P of the N vapor channels are located on an inner wall of the first side, P is a positive integer, and a sum of P and M is smaller than or equal to N.
 5. The heat dissipating device of claim 4, wherein Q of the N vapor channels are located between the M vapor channels and the P vapor channels, Q is a positive integer, and a sum of Q, P and M is equal to N.
 6. The heat dissipating device of claim 1, wherein a cross-section of each of the N vapor channels is rectangular, polygonal, circular or arc-shaped.
 7. The heat dissipating device of claim 1 further comprising a second capillary structure formed in the compensation chamber and located on an inner wall of a second side of the chamber body, wherein the second side is opposite to the first side.
 8. The heat dissipating device of claim 7 further comprising: a third capillary structure formed in the compensation chamber and located on an inner wall of the first side; and a plurality of support pillars formed in the compensation chamber and connecting the second capillary structure and the third capillary structure.
 9. The heat dissipating device of claim 8 further comprising a plurality of fourth capillary structures, each of the fourth capillary structures being formed around one of the support pillars and connecting the second capillary structure and the third capillary structure.
 10. The heat dissipating device of claim 1, wherein a pipe diameter of the first end is larger than a pipe diameter of the second end.
 11. The heat dissipating device of claim 1, wherein the heat sink comprises a plurality of heat dissipating fins. 